Gregg v Scott [2005] UKHL 2; [2005] 2 AC 176

The appellant (G) appealed against a decision that his medical negligence claim against the defendant doctor (S) failed. G had visited S because he had a lump under his arm. S negligently misdiagnosed G’s condition benign. A year later another general practitioner referred G to hospital for an examination and it was discovered that G had cancer of lymph gland. By that time the tumour had spread to G’s chest. G suffered pain and had to undergo a course of chemotherapy. He was left with poor prospects of survival. G sued S, alleging that S should have referred him to hospital and that if S had done so, his condition would have been diagnosed earlier and there would have been a high likelihood of a cure. The Court of Appeal dismissed G’s appeal. G appealed to the House of Lords.

• Could G successfully argue that loss of chance recovery is either a consequential loss derived from physical injury or a compensable head of damage itself.

The House of Lords dismissed Gregg’s appeal by a majority. The reduction in his estimated survival prospects did not establish a separate compensable loss of chance replacing the ordinary requirement to prove injury caused by negligence. His prospects had been below fifty per cent even before the negligent delay. The approach used to value future risks and chances did not dispense with the need to establish the relevant causal connection on the balance of probabilities. The majority therefore rejected the proposed recovery based on the lost prospect of a better medical outcome. This did not exclude compensation for distinct injury proved to have resulted from delayed diagnosis.

Gregg rejected a general loss-of-chance measure for a reduced prospect of medical recovery where ordinary causal proof was not established. The decision does not prevent recovery for distinct injury proved to have been caused by delayed diagnosis; statistical survival loss is not automatically a separate actionable injury.

Gregg is an important limit on importing commercial loss-of-chance reasoning into personal injury. The majority retained ordinary proof requirements despite a substantial reduction in the claimant's estimated survival prospects. Allied Maples concerns a different setting, involving a third party's commercial response. Students should also distinguish the proof of past causation from valuing future consequences once actionable injury has been established, rather than assuming probabilities are treated identically at every stage.